The proposed research is designed in response to a need to contribute to the understanding of the natural history fragile X syndrome (FXS) across the lifespan, explore effective strategies to increase participation in the existing longitudinal database by minority, underserved and adults living with FXS, and test approaches to measure cognitive and behavioral function in the FXS population. The current application is from a team of scientists, data managers and statisticians who will develop a Data Coordinating Center to manage the receipt, processing and analysis of patient, caregiver, clinician and laboratory reported data from clinics participating in the longitudinal database and other data sources. The Data Coordinating Center and the functions it carries out on behalf of the overall project will be known as Component B, which will work in close collaboration with Component A and Component C, which are funded separately. Component B and the other Components will also work in close collaboration with representatives of the Centers for Disease Control (CDC) in developing strategies, guidelines and procedures for implementing and monitoring the project. Component B will also work closely with the participating clinics throughout the United States serving individuals with FXS and their families. Component B will maintain the existing on-line data capture and storage system into which participating clinics have registered consented individuals with fragile X, and which serves as the data collection and storage system for longitudinal information collected on these participants. The on-line system will have the capacity to include the registration and longitudinal data for 450 additional participants, and wil also expand to include additional clinical information about these individuals, based on specifications provided by the other Components. Other functions of Component B include: ensuring the security of the registry and longitudinal data, establishing mechanisms for data review and quality control, conducting statistical analyses for publications and reports in response to data requests, establishing fixed data sets that will be the basis for statistical analysis, and developing de-identified data that can be shared with the research community.